Selling prints, different sizes & prices w/o diff product pages

I am a photographer trying to set up a site to sell prints from. I have run into a problem with all of the e-commerce plugins that I have tested out so far though. They only allow for one price per product. Sure, I can list different options for a product (like small, medium or large), but I need to list each option as a different price.

Every one of my prints would ideally be offered as, for example, a 5×7 at $20, 8×10 at $35, 11×14 at $50 and 12×18 at $60. I want all of these options to be available from the one product page – not 4 different product pages for each photo.

I have read an excellent tutorial on exactly how to set this up but thought that maybe there would be a less cumbersome way to approach the problem.

Update: I’m currently creating separate product pages (since I am not planning on listing a large number of different prints) and using Google Checkout to run them through since it gives me the option of listing multiple options for each product at different prices. However, I’d still be really happy to learn about something that could handle the job with a plugin.